1. Field of Invention
The present invention relates generally to gemstones. More specifically, the present invention is related to a gemstone cut.
2. Discussion of Prior Art
Diamonds are one of the most popular gemstones. One measure of the quality of a diamond is related to the cut of the diamond. The better the cut of a diamond, the higher the quality of light reflected and thus an increase in the brilliance.
FIG. 1 illustrates the general structure associated with a diamond. The basic structure can be divided into three sections: a crown 102 which forms the upper section of the diamond, a pavilion 104 which forms the lower section of the diamond, and a girdle 106 which forms the rim separating the crown from the pavilion.
FIG. 2 illustrates a prior art gemstone cut as described in U.S. Pat. No. 693,084. The patent provides for a diamond, or other precious stone having a series of quadrilateral facets a, meeting in the center, at an elevation to form an apex, a series of quadrilateral facets axe2x80x2, surrounding the series of quadrilateral facets. A second series of quadrilateral facets a2, surrounds the facets axe2x80x2 and extends to the girdle, and triangular girdle facets a3 fills the space between the points of the facets a2 and the girdle.
The U.S. patent to Huisman (U.S. Pat. No. 3,585,764) provides for a method of cutting a diamond to produce 72 pavilion facets comprising the steps of: 1) cutting four pavilion facets, 2) dividing the four into eight pavilion facets, 3) cutting the eight into sixteen pavilion facets with substantially overlapping edges, 4) polishing the girdle to a 90xc2x0 edge, 5) cutting a facet at 53xc2x0 at each overlap, 6) dividing each such latter facet into three facets such that each latter facet is provided with a diamond shape, and 7) cutting 38 facets into the girdle.
The U.S. patent to Elbe (U.S. Pat. No. 3,788,097) provides for a brilliant gem having upper and lower facets which are inclined to a girdle plane and formed by lateral surfaces of a pyramid. The angles between the lower facets and the girdle plane ranges from 37xc2x0 to 45xc2x0, and are selected such that emerging light is dispersed in a dispersion angle from 1xc2x0 20 minutes to 12xc2x0 57 minutes. The gem is also provided with a second plane parallel to the girdle plane, and contains an odd number of upper and lower facets in a ring of facets circling the gem.
The U.S. patent to Grossbard (U.S. Pat. No. 4,020,649) provides for a step cut gemstone with a straight edged polygonal shaped girdle that has a generally pyramidal base and a crown with girdle and table breaks, wherein at least one of these breaks is cut with triangular shaped facets. The angle between the plane of the girdle break of the crown and the table should be in the range from 35xc2x0 to 42xc2x0.
The U.S. patent to Andrychuk (U.S. Pat. No. 4,083,352) provides for a method for systematically and accurately increasing the brilliance and depth of color of a gemstone without the need to determine the pavilion and facet angles by trial and error.
The U.S. patent to Grossbard (U.S. Pat. No. 4,118,949) provides for a brilliantized step cut diamond that has a straight edged polygonal shaped girdle with sides and corner facets; a crown with table and a table-and-girdle breaks which are faceted; and a pyramidal base having a point culet, a culet break and a girdle break with ridges extending from the culet to the corner of the girdle. A fan with three pairs of triangular halves is disposed symmetrically about each ridge with a triangular facet in each corner of the base having an edge which is collinear with the edge of a corner facet and an apex at a ridge. The angles between the culet break and the plane of the girdle is between 30xc2x0 and 43xc2x0.
The U.S. patent to Elbe (U.S. Pat. No. 4,308,727) provides for a jewel of a brilliant type wherein a first plurality of facets are provided on the bezel and include an annular facet region whose facets are larger than 50xc2x0 and up to 90xc2x0, and another annular facet region whose facets extend from the first mentioned region towards the table and are inclined to the girdle at angles smaller than 25xc2x0. A second plurality of facets is also provided on the pavilion and includes a further annular region of facets, which are included to the girdle at angles between 25xc2x0 and 52xc2x0.
The U.S. patent to Cheng (U.S. Pat. No. 6,305,193 B1) provides for a gemstone that includes a pavilion portion, a crown portion and a girdle portion provided between the pavilion and the crown. The crown portion includes a plurality of facets provided on the surface and the crown portion has eight longitudinal sections, which collectively define it.
Whatever the precise merits, features and advantages of the above cited references, none of them achieve or fulfills the purposes of the present invention.
The present invention provides for a novel gemstone cut wherein the gemstone comprises a crown, a girdle, and a pavilion, each of which have facets disposed on them. The crown further comprises an octagonal table, which is surrounded by eight triangular star facets. In the preferred embodiment, the polishing angle of the star facets is 14.016xc2x0. In-between the star facets are disposed eight table bezels and in-between the table bezels are disposed eight mid-bezels. In the preferred embodiment, the polishing angles associated with the table bezels and the mid-bezels are 20xc2x0 and 26.18xc2x0 respectively. Lastly, in-between the mid-bezels are disposed eight girdle bezels that are close to the girdle. In the preferred embodiment, the polishing angle associated with the girdle bezel is 45.579xc2x0.
The pavilion of the present invention""s gemstone cut comprises eight concentrically arranged culet pavilion facets, and in-between the culet pavilion facets are disposed a girdle pavilion facet and a bottom small break facet. In the preferred embodiment, the polishing angles associated with the culet pavilion facet, girdle pavilion facet, and culet pavilion facet are 39xc2x0, 47.8xc2x0, and 45.536xc2x0 respectively.
The girdle of the present invention""s gemstone cut comprises eight left top half facets and eight right top half facets located in-between the girdle bezels of the crown, and eight left bottom half facets and eight right bottom half facets disposed in-between the girdle pavilion facets and bottom small break facets. In the preferred embodiment, the top half facets (left and right) have a polishing angle of 54.087xc2x0 and the bottom half facets (left and right) have a polishing angle of 55.673xc2x0.
Additionally, the gemstone of the present invention can be a precious or a semi-precious stone. In the preferred embodiment, the gemstone is a diamond.